Switch of the crossbar type



J. WHQKS Deco 26 1950 SWITCH OF THE CROSSBAR TYPE Filed Feb. 19, 19 18 JNVENTOR. .w JOHN WICKS ATTORNEY Patented Dec. 26, 1950 UNITED STATES PATENT OFFICE John Wicks, Biloxi,

Electric Laboratories, poration of Delaware Application February 19,

8 Claims.

The present invention relates in general to switching apparatus, and more particularly to improvements in switching apparatus of the cross-bar type for use in automatic and semiautomatic telephone systems.

Cross-bar switches are well known in the art and comprise essentially a plurality of contact sets arranged in intersecting horizontal and vertical rows, together with two groups of related intersecting operating bars so arranged that the actuation of one bar in each group causes the operation of a contact set at the point of intersection of the two actuated. bars. Individual magnets have generally been provided for actuating each of the operating bars, although in some instances the operating bars of a group have been actuated in a step-by-step manner by a ratchet mechanism common to the group. A particular type of cross-bar switch provides an arrangement wherein the number of operating bars of one group is one-half the number of the operating bars of the other group. In such an arrangement, the operation of a bar of the first, or smaller, group in either of opposite directions causes the selection of one or another related row of contact sets for operation by a single movement of a bar of the second, or larger, group. It is to this latter type of cross-bar switch that an embodiment of the present invention is directed.

An object of the invention is to provide an improved cross-bar switch which is economical to manufacture and simple to maintain.

Another object of the invention is to reduce in a new and novel manner the number of control elements required in a cross-bar switch.

A feature of the invention resides in the improved arrangement wherein a common cross-bar shaft controls the movements of a group of operating bars in a new and novel manner.

Another feature of the invention re ates to the provision of a step-by-step mechanism for controlling the rotative movement of a common cross-bar shaft and means for thereafter operating the rotated shaft longitudinally in either direction.

There are other objects and features of the invention having to do for the most part with the details in carrying out the foregoing. The various objects and features "of the invention will be understood best upon a further perusal of the specification taken in conjunction with the accompanying drawing in which: 1

Fig. 1 shows a perspective view of a cross-bar switch to which the present invention has been applied; I. I I

Miss,

assignor to Automatic Inc., Chicago, 111., a cor- 1948, Serial No. 9,357

Fig. 2 shows the metho of mounting selecting fingers on the vertical cross-bars and Fig. 3 is a sectional view taken along the line A-A. in Fig. 1, showing a method of slidably mounting the ratchet wheel on the common set rod.

Referring now to Fig. 1, the cross-bar switch therein disclosed is shown in diagrammatic form rather ti". an in elevation in order to reduce Fig. 1 to the simplest possible form, it being considered unnecessary for the purpose of illustrating the application of the present invention to detail such well-known structural devices as a suitable framework, bearings and mountings for the various cross-bars and common shafts, and the like. It should be understood at this time that the cross-bar switch in Fig. 1 is representative of cross-bar switches in general and that the present invention is equally applicable to other forms and arrangements of cross-bar switches. It shou d also be understood that while the cross-bar switch in Fig. l discloses only one contact set at the intersections of the vertical and horizontal rows of contact springs, a plurality of contact sets can readily be employed.

The cross-bar switch shown in Fig. 1 has four horizontal bars IUI, H32, I03, I04 and two vertical bars I20 and I25. Each of these cross-bars is rotatably pivoted in any well-known type of bearing (not shown), the bearings for each bar being rigidly mounted at two or more points on a suitable framework (partly shown). Associated with each horizontal bar is horizontal contact spring assembly 53!], and associated with each vertical bar are two vertical rows of contact springs MI and I42. Contacts are fitted at the intersecting, or cross, points of these horizontal and vertical rows of contact springs in order that electrical connections may be established between the contact springs as controlled by the operation of the vertical and horizontal bars.

Vertical bars I20, I25 each have means for selecting one or the other of the related vertical rows of contact springs I'll, I42, and horizontal bars IOI, I52, I83, I8 each have means for operating a seected contact set at t e intersection of the horizontal bar with a Vertical bar. It is,

therefore, evident that only one-half the number.

of vertical bars with respect to the horizontal bars are required. It should be understood, however, that the switch is not limited to the number of cross bars shown in Fig. 1, but maybe fitted with any required number of horizontal bars and ice corresponding number of vertical bars. The

horizontal bars in Fig. 1 are shown broken to indicate thisflexibility. e

The contact spring selecting means associated with each vertical bar comprises one selecting finger IZI for each set of contact springs I i-I and M2 accessible to the vertical bar. These fingers I2I are located opposite the related rows of contact springs use, Hi2, and are attached to the vertical bars in the well-known manner shown shown in Fig. 2. When vertical bar is rotated in a counter-clockwise direction, the fingers I2I of the vertical bar are correspondingly movedto the left underneath the shoulders M3 of the contact springs IGI. In a similar manner, when a vertical bar is rotated in a clockwise direction, the fingers I2I of the vertical bar are. correspondingly moved to the right underneath the shoulders lid of the contact springs M2.

The contact operating means associated with each horizontal bar comprises a shoulder cut-out I22 opposite each vertical bar, in which cut-outs the free ends of the respective selecting fingers I21 operate. The left-hand vertical face of cutout I22 limits the left-hand travel of finger I2I, and the right-hand vertical face of cut-out I22 correspondingly limits the right-hand travel of finger I2I. normal, or neutral, position it rests on the related cut-out I22 midway between and clearing the shoulders I43, Hit of the contact springs Iti and I 42. Rigidly attached to and forming a part of each horizontal bar IBI, I82, I63, It l is a lug I23 for providing means whereby the front member of the horizontal bar may be lifted in a vertical plane in the manner to be subsequently described. When a horizontal bar is lifted through the medium of lug I23, the cut-outs I22 of the horii',"

zontal bar are correspondingly moved upwardly and, consequently, a selecting finger I2I resting underneath either shoulder I43 of a contact spring IM or shoulder hi l of a contact spring M2 at the intersection of the horizontal bar with a vertical bar causes the related contact spring ItI or I42 to be raised thereby to make electrical contact with the related horizontal contact spring I; The horizontal contact springs I33 are fixedlv mounted and do not move when a contact spring I-II or I42 is pressed upwardly.

To rotate a vertical cross-bar in either direction thereby to select a row of contact springs It! or Hi2, a common horizontal shaft, or set rod, IE2 is provided. This set rod Iiiii is journaled in suitable bearings (not shown) in a hori zontal plane with respect to the vertical crossbars, the bearings permitting rotative and longitudinal movements of the set rod Set rod I 38) is provided with a plurality of spirally arranged pins I85, one for each vertical cross-bar. The pins I05 are rigidly mounted on set rod I00, and are so located that one pin at a time, and only one pin, will engage the open end of lever I24 of the respective vertical cross-bar. Set rod N32 is rotated in a step-by-step manner for selecting particular vertical cross-bar, by means of a magnet III? operating a stepping pawl I93 for the ratchet wheel I96.

While set rod It??? is rotative with ratchet wheel I65, ratchet wheel IE5 is slidably mounted on set rod Iiifl in order that set rod its may be shifted longitudin lly in either direction without rrespondingly shifting ratchet wheel Itfi. A twomembered bracket IISI (shown in Figs. 1 and 3) attached to the framework of the switch in any suitable manner retains ratchet wheel Ice in position with respect to magnet It? and stepping pawl I08, clearance holes in the two members of bracket I I5 permitting set rod Hill to be shiited When a, selecting finger is in the to the left or right without interference A key I26 (Fig. 3) affixed to set rod IBD and passing through a, clearance slot in ratchet wheel Itt provides means whereby ratchet wheel may cause the rotation of set rod ItII and whereby set rod I may be shifted to the left or right without affecting ratchet wheel Int.

After a vertical cross-bar such as I2t has been selected by the rotation of set rod IIII) to the position where pin IE5 at the left-hand end of set rod Ito engages the open end of lever I 2d attached to vertical bar I29, set rod IIIII is then operated longitudinally in one direction or the other dependent upon whether the fingers I2I of vertical bar I2 are to select contact springs I II or contact springs M2. The longitudinal movement of set rod IIlG to the left is controlled by magnet I9, and the longitudinal movement to the right by magnet IIB'. Both of these magnets are fixedly attached to the framework of the switch in any well-known manner, and either magnet may operate armature III. Attached to armature II I at the center point is a member H2, the free end of which rests between collars H3 and II 4 fixedly attached to set rod Itii and rotatable therewith.

When magnet IEIS is energized and attracts armature III, the free end of member II2 correspondingly presses against collar H3 thereby forcing set rod ltd to the left against the increasing tension of helical spring M5 which is loosely mounted over set rod ILIII between collar I13 and bracket I It of the switch framework. A clearance hole in bracket IIE enables set red It to move freely in bracket II 6. Pin I95 at the. left-hand end of set rod III, therefore, operates lever I24 of vertical bar I2 to the left, the balllike end of pin I and the rounded inside contour of the open end of lever I25 reducing friction between these two members to a minimum.

The rotation of vertical bar I29 clockwise, as a result of set rod Ilii! being shifted to the left by the energization of magnet H19, causes the free ends of the selecting fingers I2I of vertical bar I20 to be moved to the right underneath the shoulders I44 of the respective contact springs I42, thereby selecting the respective contact springs I 42.

When magnet III is energized and attracts armature III, the free end of member II2 correspondingly presses against collar IIQ thereby forcing set rod Ids to the right against the increasing tension of helical spring III which is loosely mounted on set rod Iiit between collar I It and bracket I it of the switch framework. A clearance hole in bracket Ilii enables set rod Iii; to move freely in bracket H8. Pin at the left-hand end of set rod IIIII, therefore, operates lever IZ I of vertical bar I25 to the right, and the resulting counter-clockwise rotation of vertical bar IZii causes the free ends of the selecting fingers I2! of vertical bar I28 to be moved to the left underneath the shoulders 523 of the respective contact springs I II, thereby selecting the respective contact springs I H.

After a vertical cross-bar such as I223 has been rotated counter-clockwise or clockwise in order to cause the selection of the related row of contact springs, I iI or the related row of contact springs It; in the manner just described, one of the horizontal cross-bars I BI, I92, IE3 or its lifted to cause the selected contact spring I I'I or at the intersection point the lifted horizontal cross-bar with vertical bar 525 to make contact with the contact spring assembly I30 associated with the lifted horizontal crossbar. A common shaft, or control rod, I50 is provided for lifting the horizontal cross-bars. This control rod I50 is journaled in suitable bearings (not shown), the bearings permitting rotative and longitudinal movements of the control rod. Control rod I50 is provided with a plurality of spirally arranged pins II, one for each horizontal cross-bar, arranged in a similar manner to that previously described for set rod I00. Control rod I50 is rotated in a step-by-step manner for selecting a particular horizontal cross-bar, by means of a magnet I52 operating a stepping pawl I53 for the ratchet wheel I50.

In a similar manner to the arrangement of set rod I 00, control rod I50 is rotative with ratchet wheel I 50, and ratchet wheel I54 is slidably mounted on control rod I50 in order that control rod I50 may be shifted longitudinally without correspondingly shifting ratchet wheel I 54. A two-membered bracket I55 (shown in Fig. 1) attached to the framework of the switch retains ratchet wheel I50 in position with respect to magnet I52 and stepping pawl I53 in a similar manner to that previously explained for ratchet wheel I00.

After a, horizontal cross-bar such as IOI has been selected by the rotation of control rod I55 to the position where pin I5I near the upper end of control rod I 55 engages lug I23 of horizontal bar I01, control rod I50 is then operated longitudinally in an upward direction through the energization of magnet I55. Armature i5? is attracted by magnet I 55, and member I55 in contact with the under face of collar I55 (collar I50 being fixedl attached to control rod I 55) correspondingly raises control rod I55 by forcin-g collar I59 upwardly against the increasing tension of helical spring I50. Helical spring I50 is loosely mounted over control rod I50 between collar I59 and bracket IBI of the switch framework, and is tensioned to cause member I58 to normally hold armature I 5'! in its retracted position. A clearance hole in bracket I5I enables control rod I50 to move freely in bracket I55.

The lifting of control rod I55 in the manner described in the preceding paragraph causes the uppermost pin I5! to raise lug I23 of horizontal bar I 5|. The horizontal face of the cut-out I22 nearest the left-hand end of horizontal bar IiiI, therefore, presses the outer end of finger I2I located near the top end of vertical bar I01 upwardly against the shoulder I53 of the related contact spring I iI or upwardly against the shoulder Hi l of the related contact spring I52 dependent upon which of the two contact springs was previously selected by the setting of vertical bar I20. Either contact spring MI or contact spring 552 is, consequently, raised thereby to mak electrical contact with horizontal contact spring assembly I30 associated with horizontal bar NH.

The holding of horizontal bar Iiil in the raised position by magnet I 55 maintains the uppermost finger I2I of vertical bar I in the engaged position, although vertical bar 525 may be returned to its normal position by the release of set rod I55. The return of vertical bar I will place the rest of the selecting fingers I2! of vertical bar I25 in the center, or neutral, position in a well-known manner. The release of set rod I05 is accomplished by de-energizing either magnet I 09 or magnet III], as the case may be. Either helical spring H5 or spring til then causes either collar I I5 or collar I It to force member II2 to the center position thereby to cause the retraction of armature III. The normal tensions of springs I I5 and III cause collars H3 and H4 to retain member H2 in the center position. The release of set rod I00 causes the left-hand pin I05 of set rod I00 to return vertical bar I20 to its normal, or neutral, position in an obvious manner.

The release of the established connection at the intersection point of horizontal bar IBI with vertical bar I20 is accomplished by de-energizin-g magnet I now holding horizontal bar MI in the raised position, thereby permitting helical spring I 50 to cause collar I59 to force member I58 downwardly. Control rod I50, consequently, is returned to its lower position and armature I5! is retracted. The release of control rod I50 permits horizontal bar I0! to be returned to its lower, or normal, position by the spring action of either operated contact spring I GI or operated contact spring I52 (as the case may be). As horizontal bar I00 reaches its lower position, the left-hand shoulder I22 of horizontal bar IOI no longer exerts pressure on the engaged finger I2I of vertical bar I 25, and this engaged finger I2I of vertical bar I20 is consequently, returned to its center, or neutral, position in a well-known manner.

Set rod I00 may be so arranged as to have a normal, or home, position and after its release by the de-energization of either magnet I59 or magnet H5 (as the case may be) may be returned to the home position through any wellknown means of automatically stepping magnet I5? until the home position is reached. Control rod I50 may also be similarly arranged to be automatically returned to a home position upon the de-energization of magnet I56.

While the present invention is disclosed in connection with but a single form of cross-bar switch, it should be understood that the various features thereof could readily be applied to other forms of switch structures without departing from the spirit thereof, and that the present disclosure should only be considered as illustrative of one embodiment of the invention.

What is claimed is:

1. in a switch, two bars mounted adjacent each other in an intersecting plane, two sets of contacts at said intersection of said bars, one of said bars having means for selecting either of said contact sets, a shaft adjacent to said bars at an angle to said one bar and having means for en- Y gaging said one bar, means for rotating said shaft thereby to cause said shaft to engage said one bar, means for moving said shaft longitudinally in either of two directions, the moving of said shaft in one of said directions causing said selecting means of said one engaged bar to select one of said contact sets, the moving of said shaft in said other direction causing said selectin means of said one engaged bar to select said other contact set, and means for causing said other bar to operate the selected contact set.

2. The switch claimed in claim 1 wherein said last means comprises a shaft adjacent to said bars at an angle to said other bar and having means for engaging said other bar, means for rotating said last shaft thereby to cause said last shaft to engage said other bar, and means for moving said last shaft longitudinally thereby to cause said other engaged bar to operate said selected contact set.

3. The switch claimed in claim 1 wherein said means for moving said shaft longitudinally in either of said two directions comprises two magnets, an armature common to both said magnets, and a lever attached to said armature and engaging said shaft, the operation of one of said mag nets operating said armature thereby to cause said lever to move said shaft in one of said directions, the operation of said other magnet operating said armature thereby to cause said lever to move said shaft in said other direction.

4. In a switch, first and second groups of bars mounted adjacent each other in intersecting planes, two sets of contacts at each of the intersections of said bars, means individual to the respective bars of said first group for selecting one or the other of said contact sets at each of the intersections of said respective bars with the bars of said second group, a shaft adjacent to said two groups of bars at an angle to the bars of said first group and having means for engaging any one of the bars of said first group, means for rotating said shaft thereby to cause said shaft to engage one of said bars of said first group, means for thereafter moving said shaft longitudinally in either direction, the moving of said shaft in one of said directions causing said means of said one engaged bar to select one of said contact sets at each of the intersections of said one engaged bar with the bars of said second group, the moving of said shaft in said other direction causing said means of said one engaged bar to select said other contact sets at each of the intersections of said one engaged bar with the bars of said second group, and means for causing one of said bars of said second group to operate the selected contact set at the intersection of said one engaged bar of said first group with said one bar of said second group.

5. In a switch, the combination of a plurality of A bars each having contact conditioning means, a plurality of B bars each having contact operatin means, said pluralities of bars arranged in intersecting rows, two contacts at each intersection point of said bars, the rotative movement of an A bar in one or another direction causing its contact conditioning means to correspondingly condition one or the other of said contacts at each intersection point of said one A bar with said B bars, the rotative movement of a B bar causing its contact operating means to operate the conditioned contact at the intersection point of said B bar with a rotated A bar, a shaft adjacent to said A bars and having means for engaging any one of said A bars, a step-by-step mechansm for rotating said shaft thereby to select one of said A bars, means for moving said shaft longitudinally in either direction to correspondingly rotate a selected A bar, a shaft adjacent to said B bars and having means for engaging any one of said B bars, a step-by-step mechanism for rotating said last shaft thereby to select one of said B bars, and means for moving said last shaft longitudinally to cause the rotation of a selected B bar.

6. In a cross-bar switch, horizontal and vertical bars, a first shaft common to said vertical bars and having means for selecting any one of said vertical bars, a second shaft common to said horizontal bars and having means for selecting any one of said horizontal bars, a selecting arm adjacent each horizontal bar on each vertical bar, a horizontal row of contacts individual to each horizontal bar and arranged in vertical columns having a first and a second vertical column individual to each vertical bar, means for initially operating said first common shaft thereby to select one of said vertical bars, means for initially operating said second common shaft thereby to select one of said horizontal bars, means for selectively operating said first common shaft to selectively actuate said selected vertical thereby to cause the selecting arms thereon to select either said first column or said second column of contacts individual to said actuated vertical bar, means for further operatin said second common shaft to actuate said selected horizontal bar, means responsive to said actuation of said selected horizontal bar for actuating the selecting arm of the actuated vertical bar adjacent said actuated horizontal bar, and means responsive to said actuation of said last mentioned selecting arm for operating the contact previously selected by said last mentioned selecting arm.

'7. In a switch, the combination of a plurality of first bars, a plurality of second bars, said pluralities of bars arranged in intersecting planes, two sets of contacts at each intersection point of said first and second bars, contact conditioning means individually associated with each of said first bars, step-by-step controlled means for selecting any one of said first bars, means for rotatin a selected first bar in one or the opposite direction thereby to cause its contact conditioning means to condition one or the other of said two contact sets at each intersection point of the selected first bar and said second bars, contact operating means individually associated with each of said second bars, step-by-step controlled means for selecting any one of said second bars. and means for rotating a selected second bar thereby to cause its contact operating means to operate the conditioned set of contacts at the intersection point of the selected second bar and a rotated first bar.

8. In a switch, two bars adjacent each other in an intersecting plane, two contacts associated with one of said bars at said intersection of said bars, said other bar having means for selecting either of said contacts, a shaft adapted for being operated in three different directions, said shaft having means for engaging said other bar, means for operating said shaft in one of said directions thereby to cause said engaging means of said shaft to engage said other bar, means for opera ing said shaft in a second of said directions thereby to cause said selecting means of said engaged other bar to select one of said contacts, and means for operating said shaft in the third of said directions thereby to cause said selecting means of said engaged other bar to select said other contact.

JOHN WICKS.

REFERENCES CETED The following references are of record in the file of this patent:

UNITED STATES PATENTS Num-er Name Date 1,551,190 Craft Aug. 25, 1925 2,238,458 Waller Apr. 15, 1941 2,350,458 l-libbard June 6, 1944 2,350,464 Keller June 6, 1944 2412,25? Gillings et al Dec. 10, 1946 

